Merge pull request #5827 from 9rnsr/fix16094

Issue 16094 - error: overlapping slice assignment (CTFE)
dlang · Jun 23, 2016 · 20e1c81 · 20e1c81
2 parents 1feaa7f + 560f606
commit 20e1c81
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Showing 2 changed files with 39 additions and 11 deletions.
diff --git a/src/dinterpret.d b/src/dinterpret.d
@@ -4198,11 +4198,16 @@ public:
 
             if (newval.op == TOKslice)
             {
-                SliceExp se = cast(SliceExp)newval;
-                Expression aggr2 = se.e1;
-                if (aggregate == aggr2)
+                auto se = cast(SliceExp)newval;
+                auto aggr2 = se.e1;
+                const srclower = se.lwr.toInteger();
+                const srcupper = se.upr.toInteger();
+
+                if (aggregate == aggr2 &&
+                    lowerbound < srcupper && srclower < upperbound)
                 {
-                    e.error("overlapping slice assignment [%d..%d] = [%llu..%llu]", lowerbound, upperbound, se.lwr.toInteger(), se.upr.toInteger());
+                    e.error("overlapping slice assignment [%d..%d] = [%llu..%llu]",
+                        lowerbound, upperbound, srclower, srcupper);
                     return CTFEExp.cantexp;
                 }
                 version (all) // todo: instead we can directly access to each elements of the slice
@@ -4254,11 +4259,11 @@ public:
 
             if (newval.op == TOKslice && !isBlockAssignment)
             {
-                SliceExp se = cast(SliceExp)newval;
-                Expression aggr2 = se.e1;
-                dinteger_t srclower = se.lwr.toInteger();
-                dinteger_t srcupper = se.upr.toInteger();
-                bool wantCopy = (newval.type.toBasetype().nextOf().baseElemOf().ty == Tstruct);
+                auto se = cast(SliceExp)newval;
+                auto aggr2 = se.e1;
+                const srclower = se.lwr.toInteger();
+                const srcupper = se.upr.toInteger();
+                const wantCopy = (newval.type.toBasetype().nextOf().baseElemOf().ty == Tstruct);
 
                 //printf("oldval = %p %s[%d..%u]\nnewval = %p %s[%llu..%llu] wantCopy = %d\n",
                 //    aggregate, aggregate->toChars(), lowerbound, upperbound,
@@ -4317,9 +4322,11 @@ public:
                     //assert(0);
                     return newval; // oldval?
                 }
-                if (aggregate == aggr2)
+                if (aggregate == aggr2 &&
+                    lowerbound < srcupper && srclower < upperbound)
                 {
-                    e.error("overlapping slice assignment [%d..%d] = [%llu..%llu]", lowerbound, upperbound, se.lwr.toInteger(), se.upr.toInteger());
+                    e.error("overlapping slice assignment [%d..%d] = [%llu..%llu]",
+                        lowerbound, upperbound, srclower, srcupper);
                     return CTFEExp.cantexp;
                 }
                 version (all) // todo: instead we can directly access to each elements of the slice

diff --git a/test/compilable/interpret3.d b/test/compilable/interpret3.d
@@ -7710,3 +7710,24 @@ auto baz15998()
 
 static assert(bar15998a == [["", ""]]);
 static assert(bar15998b == [["", ""]]);
+
+/**************************************************
+    16094 - Non-overlapped slice assignment on an aggregate
+**************************************************/
+
+char[] f16094a()
+{
+    char[] x = new char[](6);
+    x[3..6] = x[0..3];
+    return x;
+}
+
+int[] f16094b()
+{
+    int[] x = new int[](6);
+    x[3..6] = x[0..3];
+    return x;
+}
+
+enum copy16094a = f16094a();
+enum copy16094b = f16094b();